Merge branch 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git...

[pandora-kernel.git] / Documentation / scsi / hpsa.txt

diff --git a/Documentation/scsi/hpsa.txt b/Documentation/scsi/hpsa.txt
index dca6583..891435a 100644 (file)
--- a/Documentation/scsi/hpsa.txt
+++ b/Documentation/scsi/hpsa.txt
@@ -28,6 +28,12 @@ boot parameter "hpsa_allow_any=1" is specified, however these are not tested
 nor supported by HP with this driver.  For older Smart Arrays, the cciss
 driver should still be used.
 
 nor supported by HP with this driver.  For older Smart Arrays, the cciss
 driver should still be used.
 

+The "hpsa_simple_mode=1" boot parameter may be used to prevent the driver from
+putting the controller into "performant" mode.  The difference is that with simple
+mode, each command completion requires an interrupt, while with "performant mode"
+(the default, and ordinarily better performing) it is possible to have multiple
+command completions indicated by a single interrupt.
+

 HPSA specific entries in /sys
 -----------------------------
 
 HPSA specific entries in /sys
 -----------------------------
 


@@ -39,6 +45,8 @@ HPSA specific entries in /sys
 
   /sys/class/scsi_host/host*/rescan
   /sys/class/scsi_host/host*/firmware_revision
 
   /sys/class/scsi_host/host*/rescan
   /sys/class/scsi_host/host*/firmware_revision

+  /sys/class/scsi_host/host*/resettable
+  /sys/class/scsi_host/host*/transport_mode

 
   the host "rescan" attribute is a write only attribute.  Writing to this
   attribute will cause the driver to scan for new, changed, or removed devices
 
   the host "rescan" attribute is a write only attribute.  Writing to this
   attribute will cause the driver to scan for new, changed, or removed devices


@@ -55,6 +63,21 @@ HPSA specific entries in /sys
        root@host:/sys/class/scsi_host/host4# cat firmware_revision
        7.14
 
        root@host:/sys/class/scsi_host/host4# cat firmware_revision
        7.14
 

+  The transport_mode indicates whether the controller is in "performant"
+  or "simple" mode.  This is controlled by the "hpsa_simple_mode" module
+  parameter.
+
+  The "resettable" read-only attribute indicates whether a particular
+  controller is able to honor the "reset_devices" kernel parameter.  If the
+  device is resettable, this file will contain a "1", otherwise, a "0".  This
+  parameter is used by kdump, for example, to reset the controller at driver
+  load time to eliminate any outstanding commands on the controller and get the
+  controller into a known state so that the kdump initiated i/o will work right
+  and not be disrupted in any way by stale commands or other stale state
+  remaining on the controller from the previous kernel.  This attribute enables
+  kexec tools to warn the user if they attempt to designate a device which is
+  unable to honor the reset_devices kernel parameter as a dump device.
+

   HPSA specific disk attributes:
   ------------------------------
 
   HPSA specific disk attributes:
   ------------------------------